Apparatus for sealing containers



W. D. BELL APPARATUS FOR SEALING CONTAINERS Aug. 15, 1950 I 5 Sheet's-Sheet 1 Filed Dec. 10, 1946 FilediDec. 10, 1846 Aug. 15, 1956 w. D. BELL 2,518,857

APPARATUS FOR SEALING CONTAINERS,

5 Sheets-Sheet 2 INVEN TOR. llIi/Iiamfl. Bell.

BY a u Arrokgfrs Aug. 15, 1950 w. D. BELL APPARATUS FOR SEALING CONTAINERS 5 Sheets-Sheet 5 Filed Dec. 10, 1946 Aug. 15, 1950 I w. D. BELL 2,513,857

- APPARATUS FOR SEALING CONTAINERS Filed Dec. 10, 1946 5 Sheets-Sheet 4' IN V EN TOR.

axial-411100811 Aug. 15, 1950 w. D. BELL APPARATUS FOR SEALING CONTAINERS 5 Sheet s-Sheet 5 INVENTOR.

' Filed Dec. 10, 1946 Patented Aug. 15, 1950 UNITED STAT ES PATENT OFFICE APPARATUS FOR SEALING CONTAINERS Application December 10, 1946, Serial No. 715,259

combustible mixture so formed is ignited,.and the closure is sealed upon the container while the entire head-space of the container is enveloped in the highly heated products of the resulting combustion.

The present invention is a further development of apparatus for making use of this method. It has for its principal object the provision of simplified apparatus, to make possible more rapid and positive operation of the machine. This is accomplished by eliminating valves and other devices for interrupting the flow of gas, and by providing for the inherently automatic ignition of the combustible mixture formed in the head space, without the necessity of providing auxiliary igniting devices.

According to the present invention, the com- .bustible gas required for the production of the partial vacuum in the head-space of the container (or required for the operation of the machine) flows constantly during the operation of 'the sealing machine.

The gas, mixed with insufficient air for complete combustion, normally issues as a steady flame'from a suitable orifice Or burner which is so located as to direct the gas into the head-space when a container is to be sealed.

Some of the gas remains unignited at the burner tip, because of the lack of air necessary for complete combustion and during the sealing operation will enter into the head-space of the container and mix with the free oxygen therein. This free oxygen will support combustion of such unignited gas and will be consumed in the combustion thereof, as a result of the automatic ignition of the gas and air mixture in the head-space, which is brought about by the burner flame.

The particular apparatus which I preferably employ, and which will be described in detail hereinafter includes a conveyer for moving filled containers successively beneath an inclined cap chute, which is arranged to guide caps into position to be engaged by the moving'containers. V A

13 Claims. (Cl. 226-82.4)

gas burner is arranged to project a flame into the angular space formed by the cap chute and the tops of the moving containers and with the main body of the flame as nearly as possible at the point where the container engages the cap in the cap chute. Caps move down the inclined chute by gravity. However, retaining means is associated with the cap chute for preventing the lowermost cap from moving into the extreme lower end of the cap chute where it will encounter the jet of flame issuing from the burner, until a container moves into sealing position at the lower end of the cap chute. Thus, normally the gas or gaseous mixture issuing from the burnor burns freely in such a position that the heat of the combustion will not injure the cap to be applied to the next container to be sealed. When the container approaches or comes .into the sealing zone, the lowermost cap in the chute is automatically released and allowed to slide down to the extreme lower end of the chute where it will be engaged by the approaching container. The cap-retaining means is operated automatically to release the cap by the container approaching sealing position.

When the container approaches or comes into the sealing zone, the burner discharges the stream of gas and an enveloping jacket of flame into the space between the container and the closure or cap that is about to be sealed upon it. When the stream of combustible gas, mixed with a part of the air required for complete combustion, is-

sues from the orifice and burns in the air before encountering the cap or container, the resulting flame consists of a core of unburned mixture surrounded by a jacket or envelope of flame, the combustion being sustained by oxygen obtained both from the primary air introduced into the burner with the gas and from secondary air from the surrounding atmosphere. Normally, this envelope of flame completely encloses the stream of unignited mixture as it issues from the burner orifice. However, as soon as the flame jet encounters the closure or cap to be applied to the container, as it slides into the extreme lower end of the cap chute, and the walls of the container, as it moves beneath the lower end of the chute, the integrity of the flame envelope is broken by the resulting turbulence and by impingement of the jet upon the relatively cold surfaces of the cap and container, and unburned gas mixture from the inner core of the jet spills out into the headspace of the container. This action takes place as the closure is applied to the container. Sterilization of the closure and head-space of the container results and a partial vacuum is formed within the head-space by cooling and contraction of the gases therein.

The preferred embodiment of my invention is illustrated in the accompanying drawings wherein similar characters of reference designate corresponding parts and wherein:

Figure l is 'a side -.elevational view, partly broken away, or a sealing machine embodying my invention. 7

Figure 1a is a horizontal sectional view taken along line Iala of Figure 1 through the ,fuel supplying mixer and blower.

Figure 2 is a plan View of the machine :of Figure 1.

Figure 3 is an enlarged side elevational view of the sealing head and associated mechanism.

Figure 4 is an end view of the structure illustrated in Figure 3.

Figure 5 is a plan view of the structure illustratedin Figures'3 and 4.

Figure=6 is .a plan view of part of the structure :shown in Figure 3 and taken substantially along line :.66 .ofiFigure .3.

Figure ,7 is .a sectional view taken through the cap chute substantially along line 1-1 of Figure,3..

Figure 8 :is a detailed view, mainly in vertical section, illustrating how the burner normally burn without contacting the lowermost cap in the chute and illustrating how the 'conainer actuates the cap-retaining means to release the cap asit moves into association with the lower end of the cap chute.

Figure 9 is a'view similar to Figure '8 butshow- .ing the released cap in the extreme lower end of the cap chute with the burner flame impinging upon the lower surface thereof.

Figure 10 is a view similar to Figure 9 and illustrating .hoW the cap leveling and pressing means begins to function :as the container continues to move beyond the lower end .of the cap chute.

Figure :11 is .a view similar to Figure 1.0 illustrating the container moved farther :a-long relative to the lower end of the cap chute and illustrating the cap almost in sealing position on the upper end of the container.

Figure 12 is a perspective view :of the lower end of the cap chute and the associated container feeding or conveyingamechanism.

Figure 18 is a diagrammatic View illustrating the condition of the flame jet before it impinges upon the cap.

Figure 14 is a view similar to Figure 13 but showing the condition of the flame jet when it impinges upon the cap which is being applied to thecontainer.

With reference to the drawings, and particularly to Figures .1 and 2, I have illustrated one form of my apparatus as comprising generall a supporting table i, a conveyer unit 2, a container feeding and guiding unit 3, and a sealing head unit 4. The conveyer 2 and the feeding and guiding unit 3 will cooperate to feed the .conta-iners continuously into association with the unit A. At the unit 4, a cap will be guided into association with the upper end of the container, a flame jet will be directed beneath the cap, creating a combustible mixture in the head-space of the container which will be ignited, and the cap will be guided into sealing position on the container as combustion occurs. The rapid drop in pressure in the head-space of the container resulting from cooling and contraction of the 'fit between it :and the rail :52.

gases remaining in the head-space, will aid in drawing the cap down into sealing relationship to the container. With some types of caps no further action will be required to seat the cap on the container. However, in other cases, it may be desirable to subject the cap to mechanical sealing pressure to permanently seat the cap on the container. 'For example, it maybe desirable to subject the cap to mechanical sealing pressure in a sealing unit 5, as shown in Figure 1, which is associated with the conveyer 2 beyond the sealing head-4.

The table I may be of any suitable structure .but, .as commonly shown in Figure 1, includes an upper shelf 5, an intermediate shelf 7 and a lower shelf -8. The conveyer 2 is of any suitable type of endless conveyer and is recessed within the upper shelf 6. The lower flight of the conveyer will rest on rollers 9 carried by the shelf 7. The conveyer is driven continuously by a suitable drive 10 extending :irom' a variable speed electric 51110130141 which issupported on thelower shelf 8.

The guiding and feeding unit 3 comprises a guide rail 12 which extends along one side of the conveyer 2 and .spaced vertically rthereabove. On't'he-oppos'ite side-of the conveyer and extending 'longi-tudinallythereof is a container feeding and spacing screw l3. The rail f2 and screw l3 .arepreferably vertically adjustable by suitable mechanismptnot shown). The drive i0 is con- ;nected to the screw '13 so that the screw will be driven continuously in properly timed relation- ;ship to the conveyer 2. Since the detailed structure of this unit .3 is not a part of the present invention, 'further description is believed un necessary. Containers placedat random on the loading end of the conveyer '2 Will be moved progressively by the continuously moving conveyer and thescrew I13 into association "with the sealing head 4. The screw l3 will also :be adjustable laterally'so that various diameter containers can The screw will :cooperate with the conveyer .2 to feed the con- .ta-inersin uniform spaced relationship to the .unit 4.

The sealing head unit 4 is illustrated best in Figures :1, 8, 4, and 8 to 12, inclusive. This unit is supported .by a vertically disposed standard M which is bolted to the top shelf 6 of "the machine. This unit includes a downwardly :and forwardly inclined cap chute I5 which is suitably attached .to'the standard 1 3. The chute l5 will be spaced laterally of the standard It. a sufficient distance to position it properly over the path of movement of the containers carried by the conveyer .2. Furthermore, the chute will be disposed at a proper height'to locate the lower end thereof at the proper level above the conveyer 2, depending upon the height of the containers being sealed. The chute l5 will support the caps l6 which are disposed therein in edge-to-edge relationship.

The caps which are used for sealing the containers may be of various-types although in the drawings I have illustrated side seal caps, as shown best in Figure 14. These side seal caps are commonly used for sealing glass jars of the type shown in the drawings and indicated by the numeral 11. This glass jar is provided with a reduced mouth having a sealing edge l8 with which the sealing gasket H) of the cap cooperates. The gasket is disposed within a groove formed in an enlarged annular bead 20 on the lower edge of the skirt of the cap.

I provide means for preventing the lowermost 5.. cap in the chute from reaching the extreme lower end of the cap chute until a container moves into sealing position at the lower end of the chute. This means is illustrated best in Figures 3 to 7 and 12 and comprises a cap-retaining unit indicated generally by the numeral 2|. It comprises a. finger-carrying block 22 of elongated form which extends along one side of the chute 15 adjacent the lower end thereof and is spaced therefrom. This block 22 is pivoted by means of a'vertical pin 23 to a supporting car 24 which extends laterally from the cap chute l5. The block 22 carries a lower inwardly extending capengaging finger 25 and an upper inwardly extending cap-engaging finger 26 which are spaced apart a distance greater than the radius but less than the diameter of the cap. These fingers extend through slots 21 formed in the adjacent outer wall of the cap chute.l5. When member 22'is swung about the axis of pivot .23, one of the fingers 25 or 26 will be projected into the.

chute into position to engage a cap tending to slide downwardly through the chute. As shown best in Figure '7, when one of the fingers is projected into the chute, the other will be withdrawn to such a position as not to interfere with movement of the caps in the chute. A compression spring 28 is disposed between the side of the chute and the inner side of member 22,

adjacent the upper end thereof, so as normally to project the lower finger 25 into the chute and to withdraw the upper finger 26 from the chute. Consequently, the lowermost cap in the chute l will normally feed downwardly through the chute until the lower finger 25 engages the cap and prevents further downward movement.

For swinging the member 22 about the pivot 23 to release the lowermost cap, I provide a lever 29. This lever is attached to a collar 39 which is keyed on the lower end of pin 23, it being understood that the member 22 is keyed on the upper end of the pin and that the pin rotates in ear 24. This lever 29 extends downwardly and forwardly to a point adjacent the extreme lower end of the cap chute l5, as shown best in Figure 12. The lower end of the lever 29 carries an inwardly extending container-engaging finger 3!. This finger is horizontally disposed and is of such size that it normally projects into the path of movement of the containers carried by the conveyer 2; This finger 3| is so located relative to the lower end of the cap chute that a container moving into sealing position will engage it just before the. forward edge of the neck of the container reaches the extreme forward and lower end of the cap chute 15, as shown best in Figure 8.

When the container engages the finger 3|, the lever .29 is swung outwardly, thereby causing the upper end of the member 22 to swing inwardly and the lower end to swing outwardly. This moves the lowermost finger 25 out of the cap chute, permitting the lowermost cap to slide on downwardly to the extreme lower end of the cap chute and, at the same time, moves the uppermost finger 26 into the cap chute engaging the cap next above and preventing downward sliding movement thereof. The released cap slides downwardly to the extreme lower end of the cap chute until it engages oppositely disposed inwardly extending pins 32 at the extreme lower end of the chute. During the release of the cap and its downward movement, the container continues to move past the finger 3|. However, the release and downwardmovement of the cap cc;-

curs so speedily that the released cap will move into a position in the cap chute ahead of the oncoming container, as shown best in Figure 9. Thus, the forward edge of the neck of the container will engage the forward part of the skirt of the cap, as shown in Figure 9, and will withdraw the cap from the chute. As the cap is withdrawn from the chute by the container, it is lifted above the pins 32, as shown best in Figure 10. As soon as the container passes completely beyond the finger 3|, the fingers 25 and 26, carried .by member 22, will be returned to their original positions relative to the cap chute. The lowermost cap in the chute will now be permitted to move past the finger 26 and downwardly in the chute until it engages finger 25.

During the withdrawal of the cap from the lower end of the chute, it is gradually leveled into horizontal position and pressed against the upper end. of the container. I provide means associated with the lower end of the cap chute for this leveling and pressin operation. This means includes apair of leveling tongues 33 (Figure 12) which are disposed between the side walls of the chute and are inclined downwardly and forwardly in substantially the same plane as the inwardly extending cap-supporting flanges 34 of the cap chute, The lowe extremities of these tongues 33 are spaced a short distance above the extreme lower ends of the flanges 34 of the chute. Supported within the cap chute above the tongues 33 and adjacent their lower ends is a cap-depressing member 35. This member 35 includes a narrow upper portion 36 which is disposed between the sides of the cap chute and is carried by a pivot pin 36a which is transversely disposed and has its ends supported in the sides of the chute. The lower end of member 35 is provided with laterally extending ears 31 which will normally rest on the reduced extremities 38 of the sides of the chute. As the cap is being withdrawn from the chute, the member 36 will be swung upwardly slightly and the weight of member 36 will exert a downward pressure on the cap and, particularly on the rear edge thereof. This will prevent the rear edge of the cap from being tilted upwardly during withdrawal of the cap from the chute.

A second cap depressor 39 is associated with the lower end of the cap chute. This cap depresser 39 is pivoted by means of a transversely extending pin 40 to the upstanding lugs 41 provided on the upper edges of the sides of the chute directly behind the reduced portions 38. The member 39 includes a forwardly and downwardly extending supporting portion which carries on its end an inverted U-shaped cap-contacting member 42. The dependin portions of member 42 will engage the upper surface of the cap adjacent its forward edge, as it is being withdrawn from the cap chute. The member 39 has a rearwardly extending tongue 43 to which the lower end of a tension spring 44 is anchored. The upper end of the spring 44 is anchored to an inverted U-shaped bracket 45 which is bolted to the upper edges of the sides of the cap chute l5 behind the lugs 4|. An adjustable depending stop screw 46 is carried by member 45 and engages the top surface of tongue 43 to limit upward swinging movement thereof which is brought about by the spring 44. Thus, spring 44 will keep member 42 in its lowermost position. However, member 42 is free to move vertically against the force of spring 44 as a cap is withdrawn from the capchute.

Normally, the cap depressers 35? and 39 will be in the relative positions, indicated in Figure 8. When a cap is released, it slides into. the lower end. of the. cap chute, and movement of the cap is, stopped by pins 32' so. that it will be in the position indicated in Figure 9. As the container engages the cap and starts to withdraw it, the member 35 continues to exert downward pressure on the cap, due to its weight, causing it to contact tongues 33 and the cap-contacting member 42' of depresser 39 will engage the top surface of the cap as the container withdraws it from the chute. During continued withdrawal of the cap bythe container, as shown in Figure 10, the member 52 resiliently engages the forward part of the cap and the member 35 engages the rear part of the cap and keeps it in contact with the tongues 33. This causes the cap to gradually move into horizontal position as it is withdrawn from the chute. When, as shown in Figure 11, the cap is pulled completely off the tongues 33, the member 42 will serve to pres it down completely into horizontal position where it will seat on the upper end of the container.

In order to sterilize the cap and the container, as the cap is being withdrawn from the chute, and in order to create the desired partial Vacuum within the container, I provide the stationary burner 41 which is associated with the lower end of the cap chute, as shown best in Figures 1,' 3, and 8 to 11, inclusive. The burner 4'! is carried on a support 48 which is bolted to the rear side of the cap chute adjacent the lower end thereof. It is disposed in a socket member 49 attached to member :48. and is adjustable axially in this member 19, it being held in adjusted position by means of a set screw 56. The burner will be so supported that it will extend downwardly and forwardly slightly and its forward edge will be disposed in alignment with the space between the two tongues 33, as shown best in Figure 7. Since the member 42 is of inverted U-form, the jet issuing from the burner will have substantially no eflect thereon nor on the tongues 33.

The burner, as shown best in Figure 13, comprises a main tube which has a tip disposed within its outer end. The tip 5! has a main passage 52 therethrough and cooperates with the main tube to form a surrounding annular passage 53. The passage 53 has inlet openings 54, formed in member 5!, and a circular outlet slot 55, formed between the tip and the main tube at their outer ends. In operation of this burner tip, the main stream of combustible mixture issues from a. passage 52 with considerable velocity and will form the central cone C of the flame jet J which will consist of unburned mixture. The gas mixture which enters through openings 54 with considerable velocity will expand in passage 53, where its velocity will be decreased, so that it will, flow slowly through slot 55 thereby insuring that a continuously burning envelope E, which encloses cone C, will be formed on the burner tip, as shown in Figure 13.

The fuel line 56 leading to the burner 47, as shown in Figure 1, includes a flexible section 5?, adjacent the burner, to permit the necessary adjustment of the burner in the socket member 49. This fuel line 56 is connected to a blower and mixer unit 57a which is carried by the lower shelf 8 of the table. The unit 510,, as shown in Figures 1 and 1a, comprises an electric motor 58 which drives a fan 59. The fan includes acylindrical casing 60 which has a reduced extension 6| on its upper side that forms a mixing-cham- 82 ber. This extension 6| has an air inlet- 62, the size of which may be varied by an adjustable plate 63. The fan 59 rotates in a clockwise direction and comprises a plurality of blades curved as indicated. A gas line 64 is connected to the casing extension 61 but it will be noted that line 56 is connected to a main part of the casing 60. Thus, when the fan rotates, it draws gas from line 64 and air through inlet 62 into the extension 6|, where the gas and air mingle, and then down into the main part of casing, from which it is forced through line 56. The line 54 is provided with a needle valve 65 for regulating the amount of gas entering the casing. Thus, by regulating the needle valve 6.5 and/or air inlet 52, the proportion of gas to air and the volume of the mixture entering line 56 may be regu lated.

Normally, the lowermost cap in the chute will be spaced above the extreme lower end thereof by the finger 25-. The gas or gaseous mxture being discharged from the burner tip will flow cone stantly, and as shown in Figure 13, the burner will produce the jet J of flame. Since the cap is held at a point spaced from the lower extremity of the chute by the flnger 25,, as shown in Fig-v ure 8, the jet will not impinge upon such cap and, therefore, will not injure the cap. Also, as previously indicated, the jet will have substan-. tially no eiTec-t on the tongues 33 or on the member 42. The burner is supplied with the combustible mixture :by the unit 510, the mixture including insufiicient air for complete combustion of the gas. Consequently, the jet J, as shown in Figure 13, will consist of a cone C- of unburned gas surrounded by a jacket or envelope E- of flame, the combustion of the envelope of flame being sustained by oxygen obtained both from the primary air introduced into the burner with the gas and from the surrounding atmosphere. This envelope of flame normally completely encloses the stream of gas mixture as it issues from the burner tip, as shown in Figure 13. The burner supplies a constantly burns ing jet but because of the normal location of the cap no injury thereto will result.

As the container, moved along by the conveyer 2,, moves under the lower end of the cap chute, as previously indicated, it releases the lowermost cap and allows. it to slide downwardly into. the position indicated in Figure 9. The cap slides down in front of the jet J of flame issuing from the burner. As soon as the flame jet J encounters the cap on the container, the integrity of the flame envelope E, is broken by the resulting tur bulence, as shown in Figure 14, and by impingee ment of the jet upon the relative cold surfaces of the cap and container. Consequently, u-nburned gas mixture from the inner cone 0 of the jet spills out into the head-space of the con-. tainer and mixes with the free oxygen therein to produce a completely combustible mixture, such oxygen supporting combustion of such gases and being consumed in the combustion thereof. Automatic ignition of the gas and air mixture in the head-space results from the normally burning portion of the jet. This takes place, as shown in Figures 10, 11 and 14, as the cap is being withdrawn and leveled by continued movement of the container relative to the cap chute. Combustion of the charge not only expands and displaces the air in the head-space, but also consumes the oxygen therein. As combustion subsides, and expansion is substantially complete, the cap will drop and will be pulled down into level position and also will be pressed down on iii of. the lowermost cap: in the chute: and the other of said fingers being adapted to engagethe lower edge or the capnext above in the chute, said v means for actuating the cap-retalning means comprising a: member. connected to said fingers for producing such movement thereof, said'memher being provided with a finger which is engaged successively by containers moved into: 'associationi with the-lower endof'said cap chut'e:

11; Apparatus. accordingto claim 9 wherein the fuel-supplyingmeans: comprises a mixer and blower unit which supplies-air and gas to the burner, the air being supplied inamounts insuf ficient for complete combustion of the gas;

12; Apparatus according toclaim 9' wherein; the burner comprises a central core for high velocity gas mixture and a surrounding passage for low velocity-mixture.

13'; Apparatus according toclaim 9 wherein the lower end of the cap chute is provided: with means for leveling the cap and for pressing it down into. sealing relationship with the container as:v it is withdrawn by the container.

WILLIAM D. BELL.

REFERENCES CITED lihe following references are of record in the file of this patent:

UNITED STATES PATENTS the container by member 42. The container, head space andcap will be sterilized by the intense heat developed during the combustion of the mixture of air and gas beneath the cap and in the headspa'c'e. When the sealed container moves out of range of the jet J, the jet will resumo the form illustrated in Figure 14 with the inner cone of unburned mixture C completely enclosed by the envelope E of flame.

As previously indicated, it may be desirable to subject the cap on the sealed container, after it leaves the sealing head d, to mechanical sealing pressure in the sealing unit 5. This sealing unit comprises an endless sealing belt 66 which is driven continuously at the same linear speed and in the same direction as the conveyer 2. The drive l will b'connected in a suitable manner to the belt 66 for driving it properly. The belt 66 is slightly higher at its inlet end than at its outlet end and is at a proper height relative to the conveyer 2 to gradually exert downward pressure on the caps as the containers move beneath it. Thus, the caps will be permanently seated on the containers.

It will be apparent that I have provided a simple, effective and low cost machine for continuously vacuumizing and sealing containers. Because of the novel manner in which the combustible gas is introduced into the head-space of each container, a very great simplification of the machine results. No valves or other devices for the control of the flow of gas into the headspace of the container are required. Furthermore, the gas is introduced into the head-space in such a way that ignition takes place automatically and no special ignition apparatus is required.

Various other advantages will be apparent from the preceding description, the drawings and the following claims.

Having thus described my invention, what I claim is: r

1. Apparatus for closing and sealing a container comprising a cap-feeding unit, a burner associated with said cap-feeding unit, means for constantly supplying said burner with fuel to provide a constantly burning jet of flame, means for moving a container into association with said cap-feeding unit, means forming a part of said unit for retaining a cap which is to be applied to said container in such a position that the burner jet will not impinge thereupon, and means for actuating said cap-retaining means to release said cap and permit it to move into position to beimpinged by said burner jet in association with the container which is to receive said cap.

2. Apparatus for closing and sealing a container comprising a cap-feeding unit, a stationary burner associated with said cap-feeding unit, means for constantly supplying said burner with an air and gas mixture to provide a constantly burning jet of flame, means for moving a container into association with said cap-feeding unit to receive the cap to be sealed thereon, means forming a part of said unit for retaining a cap which is to be applied to said container in such a position that the burner jet will not impinge thereupon, and means actuated by movement of the container into association with said cap-feeding unit for actuating said cap-retaim ing means to release said cap and permit it to move into position to be impinged by said burner jet in association with the container as it receives the cap.

3. Apparatus according to claim 2 wherein the mean is: su p in a r a d as. to. the burner supplies iinsufiicient air for complete oombustion of the gas.

4. Apparatus according to claim 5 wherein the burner comprises a central core for high velocity gas mixture and ag-surrounding passage for low velocity mixture f 5. Apparatus for closing and sealing containers comprising an inclined cap chute for feeding caps successively into position at the lower endof the chuteto be engaged by the upper endsof containers moved successively into association therewith, means for so moving the containers, a stationary burner associated with the lower end of .the cap chute, means for supplying fuel to said burner constantly so that the burner will provide a constantly burning jet, said burner being so located relative to the cap chute that the jet will be directed beneath the cap that moves into the lower end of the chute, cap-retaining means associated with the chute and normally preventing the lowermost cap in the chute from moving into the extreme lower end of the chute where the burner jet will impinge upon the lower surface thereof, and means for actuating said cap-retaining means upon movement of a container into association with the lower end of said chute to release the cap and permit it to be engaged by said container.

6. Apparatus according to claim 5 wherein the fuel supplying means comprises a mixer and blower unit which supplies air and gas to the burner, the air being supplied in amounts insufficient for complete combustion of the gas.

7. Apparatus according to claim 5 wherein the burner comprises a central core for high velocity gas mixture and a surrounding passage for low velocity mixture.

8. Apparatus according to claim 5 wherein the cap-retaining means is actuated to release the cap by the container as it moves into association with the lower end of the chute.

9. Apparatus for closing and sealing containers comprising an inclined cap chute for feeding skirted caps in edge-to-edge relationship with their skirted sides downwardly into position at the lower end of the chute where the skirt of the cap will be engaged by the upper end of a container moved into association therewith and the cap will be withdrawn by the container, means for moving the containers successively into association with the lower end of the cap chute, a stationary burner disposed behind the cap chute at the lower end thereof and directed forwardly towards the cap chute, means for supplying fuel to said burner constantly so that the burner will provide a constantly burning jet, said burner being so located relative to the cap chute that the cap which moves into the lower end of the chute will move through the jet and the jet will impinge on the lower surface thereof while in the chute, cap-retaining means associated with the chute at a point spaced above the lower end thereof and normally preventing the lowermost cap in the chute from moving into the extreme lower end of the chute where the burner jet will impinge upon the lower surface thereof, and means actuated by a container moving into association with the lower end of said chute for actuating said cap-retaining means to release the cap and permit it to be withdrawn from the chute by said container.

10. Apparatus according to claim 9 wherein the cap-retaining means comprises a pair of fingers which are alternatively movable into the cap chute to engage a cap therein, one of said fingers being adapted. to engage the lower edge Certificate, of Correction Patent No. 2,518,857 August 15, 1950 WILLIAM D. BELL It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 10, line 3, for the claim reference numeral 5 read 2;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 20th day of March, A. D. 1951.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

